To prepare the horchata mix let the rice soaking with the cinnamon overnight or for 5 hours at least.
Once the soaking time is up, pass everything to the blender. Blend thoroughly for a couple of minutes.
Strain the mix with a fine strainer, helping yourself with a spat to speed up the process.
Add sweetened condensed milk with half a cup of the horchata mix. Mix well and transfer to a small pot over low heat.
Add unflavored gelatin powder and dissolve by constantly moving with a spoon or a spatula. Just make sure that your horchata doesn't simmer nor boil. Now, let's boost the flavor by adding a bit of vanilla.
Once the gelatin dissolves pour the mix back into the bowl.
Before whipping the cream chill a bowl for 15 minutes in the freezer. Then, to make the whipped cream, beat the heavy cream at high speed for about 5 minutes, until you see peaks forming. Add powdered sugar for better consistency and continue beating.
Gradually fold the whipped cream into the horchata mix with a spat in delicate strokes. Then cover the bowl with a lid or plastic wrap and stick it in the fridge for at least 2 hours.
I used sundae glasses to serve the mousse but you can choose any other that you like.
Add a layer of crushed Maria cookies at the bottom of the glass.
Fill a resealable bag with the mousse mix and cut a corner to use it as a piping bag.
Make lovely swirls over the crushed Maria cookies layer and fill to the top.
Finish decorating by adding cinnamon powder and a cinnamon stick.
Ta-dah! Creamy and lovely horchata mousse!